1.) Chinchillas need a cool climate to survive. They cannot be kept outside! If your home/chinnie room is between 60-70 degrees year-round, perfect! If your chinchilla gets warm, it can get heatstroke and die within minutes. Have a contingency plan in case your AC or power goes out - you will need to keep the chins cool no matter what - even if that means temporarily relocating the chinchillas! If you like it warm in your house, a chinchilla may not be the right pet for you.
2.) Chinchillas should be fed a high quality chinchilla food, not food designed for other small animals. Too many treats (raisins, nuts) can make your chinchilla sick as well. They also need fresh timothy hay as a main part of their diet.
3.) Chinnies are energetic, yet delicate. They bounce around a lot, but rough handling can easily hurt a chinchilla. Seriously not recommended for children under 10.
4.) Chins are hypo-allergenic. If you have a reaction, it may be the dustbath sand, but it won't be the chinchilla itself.
5.) They like buddies. Two girls together are a good match. A girl and a boy, and you're in the breeding business. Two boys with no girls will also get along. All need to be introduced properly, or raised together. They need to be caged next to each other for 1 week, then clean cages & swap the chins to the other cages. After 1 week of that introduce them in a neutral area (clean cage) and watch for disagreements. If they seem agitated, separate immediately and begin the entire process again. However, some chinchillas are loners and do not prefer company.